There are many juicy disclosures in Double Down: Game Change 2012 that undoubtedly will set Washington politicos' hearts fluttering.

In their new book about the last presidential campaign, Mark Halperin and John Heilemann reveal that the White House polled and focus-grouped everything under the sun, including the possibility of having Vice President Biden and Secretary of State Hillary Clinton switch roles. Adding Clinton to the ticket, however, didn't materially improve President Obama's odds, they write.

They unveil the source of Senate Majority Leader Harry Reid's famous charge that GOP presidential nominee Mitt Romney had not paid any taxes in 10 years: Jon Huntsman Sr., the father of one of Romney's early GOP primary rivals.

And they offer some interesting detail of Biden's chafing to play a larger role in the administration while demonstrating that the vice president's ambition for a 2016 run is very real.

But perhaps the most evocative moments come when Halperin and Heilemann dig into the episodes when Obama seemed to be his own worst enemy.

Love him or hate him, Obama proved in his 2008 run to be one of the clutch campaigners of our time. But for a long moment during the final stretch of the campaign last October, the president looked as if he might blow it.

It started with his lousy performance at the first debate in Denver, when Obama appeared ill-prepared and simply outsmarted by Romney, whose dismal campaign was brought back to life by Obama's epic meltdown in the Mile High City.

Obama, of course, recovered in the second debate at Hofstra University on Long Island and went on to an electoral landslide.

But Halperin and Heilemann report that the situation for Team Obama just weeks before Election Day was far more perilous than outsiders could ever imagine.

In the lead-up to second debate, they write that "No Drama" Obama was having an existential crisis with less than 48 hours before what the campaign saw as perhaps the most pivotal point in his bid for re-election.

The president reverted to his Denver form during his second-to-last mock debate before Hofstra. He was emotionally flat and unable to connect with the voter stand-ins for a town-hall-style debate. Obama also rambled with answers that seemed "utterly devoid of message."

The Team Obama brain trust - led by his longtime advisers David Axelrod and David Plouffe - were worried, and with great reason.

The next day, Axelrod, Plouffe and Ron Klain, a former Biden aide turned debate coach, decided to stage an intervention with Obama. The president's response was startling.

It was well-known that Obama despised the theatrics of politics. But even more surprising, Obama, according to Halperin and Heilemann, acknowledged to his brain trust that he worried that his second-term agenda - much as Republicans groused - was thin gruel.

Obama even told his team that he wondered if he was even properly "wired" for the awkward pageantry of debate. The extraordinary moment wasn't lost on the brain trust. Klain said he realized they were entering uncharted territory.

"In October of an election year, on the eve of a pivotal debate, the president wasn't talking about tactics or strategy, about this line or that zinger," the authors observe. "He was talking about personal contradictions and ambivalence, about his discomfort with the campaign he was running, about his unease with the requirements of politics writ large, about matters that were fundamental, even existential."

The astounding moment, like the rest of the near-flawless narrative, is the product of 500 interviews with more than 400 individuals between 2010 and 2013.

As interesting as their insights into Obama, their dive into a Republican party that edged toward dysfunctional during the last election cycle may be even more valuable looking toward 2016.

The inevitability of Romney, as has been thoroughly reported, was hard for the party - which shifted sharply to the right after Sen. John McCain's loss to Obama in 2008 - to swallow. But Halperin and Heilemann add new polish to how much the right abhorred the thought of Romney as their standard-bearer.

They also provide new details in the unbearable slog Romney's team had vetting New Jersey Gov. Chris Christie as a vice presidential candidate and the back-channel efforts to draft a "white knight" candidate to rescue the party as Romney struggled in some of the early primaries.

The work is billed as a sequel to their outstanding best seller Game Change , which chronicled the rise of Obama and the astonishing decision by McCain to pick a rather obscure politician (at the time) from Alaska named Sarah Palin to be his running mate.

In the pantheon of campaign books, Game Change is among the best. It didn't hurt that Halperin and Heilemann, political journalists from Time and New York magazines, respectively, had amazing material to work with for the 2008 campaign book.

How do you match chronicling the rise of a young charismatic politician who would make history as the first African-American to reach the White House by knocking off the wife of the most beloved Democratic politician since John F. Kennedy and a Republican war hero to get there?

The 2012 election cycle certainly resembled a three-ring circus at times. But the intrusions of Donald Trump's birther-ism rants, Rick Perry's inarticulateness, and Newt Gingrich's line of credit at Tiffany's can't hold a candle to McCain's decision to pick Palin in terms of zaniness or the pathos of the Obama-Clinton rivalry.

Yet Heilemann and Halperin's ability to get behind the scenes and into Obama's head makes Double Down nearly as riveting as their first work.